Question

Prometheus在Docker容器（版本18.09.2，内部版本6247962 ，下面的docker-compose.xml中运行）上，并且抓取目标位于由Python 3创建的localhost:8000上脚本。

针对失败的抓取目标（localhost:9090/targets）获得的错误是

获取http://127.0.0.1:8000/metrics：拨打tcp 127.0.0.1:8000：getsockopt：连接被拒绝

问题：为什么Docker容器中的Prometheus无法抓取在主机（Mac OS X）上运行的目标？我们如何才能在docker容器中运行Prometheus来抓取主机上运行的目标？

尝试失败：尝试在docker-compose.yml

中进行替换

networks: 
  - back-tier
  - front-tier

使用

network_mode: "host"

但是我们无法访问localhost:9090上的Prometheus管理页面。

无法找到类似问题的解决方案

Getting error "Get http://localhost:9443/metrics: dial tcp 127.0.0.1:9443: connect: connection refused"

docker-compose.yml

version: '3.3'

networks:
  front-tier:
  back-tier:

services:

  prometheus:
    image: prom/prometheus:v2.1.0
    volumes:
      - ./prometheus/prometheus:/etc/prometheus/
      - ./prometheus/prometheus_data:/prometheus
    command:
      - '--config.file=/etc/prometheus/prometheus.yml'
      - '--storage.tsdb.path=/prometheus'
      - '--web.console.libraries=/usr/share/prometheus/console_libraries'
      - '--web.console.templates=/usr/share/prometheus/consoles'
    ports:
      - 9090:9090
    networks:
      - back-tier
    restart: always


  grafana:
    image: grafana/grafana
    user: "104"
    depends_on:
      - prometheus
    ports:
      - 3000:3000
    volumes:
      - ./grafana/grafana_data:/var/lib/grafana
      - ./grafana/provisioning/:/etc/grafana/provisioning/
    env_file:
      - ./grafana/config.monitoring
    networks:
      - back-tier
      - front-tier
    restart: always

prometheus.yml

global:
scrape_interval:     15s 
evaluation_interval: 15s 

external_labels:
    monitor: 'my-project'

- job_name: 'prometheus'

    scrape_interval: 5s

    static_configs:
        - targets: ['localhost:9090']


- job_name: 'rigs-portal'

    scrape_interval: 5s

    static_configs:
        - targets: ['127.0.0.1:8000']

在http://localhost:8000/metrics处的输出

# HELP python_gc_objects_collected_total Objects collected during gc
# TYPE python_gc_objects_collected_total counter
python_gc_objects_collected_total{generation="0"} 65.0
python_gc_objects_collected_total{generation="1"} 281.0
python_gc_objects_collected_total{generation="2"} 0.0
# HELP python_gc_objects_uncollectable_total Uncollectable object found during GC
# TYPE python_gc_objects_uncollectable_total counter
python_gc_objects_uncollectable_total{generation="0"} 0.0
python_gc_objects_uncollectable_total{generation="1"} 0.0
python_gc_objects_uncollectable_total{generation="2"} 0.0
# HELP python_gc_collections_total Number of times this generation was collected
# TYPE python_gc_collections_total counter
python_gc_collections_total{generation="0"} 37.0
python_gc_collections_total{generation="1"} 3.0
python_gc_collections_total{generation="2"} 0.0
# HELP python_info Python platform information
# TYPE python_info gauge
python_info{implementation="CPython",major="3",minor="7",patchlevel="3",version="3.7.3"} 1.0
# HELP request_processing_seconds Time spend processing request
# TYPE request_processing_seconds summary
request_processing_seconds_count 2545.0
request_processing_seconds_sum 1290.4869346540017
# TYPE request_processing_seconds_created gauge
request_processing_seconds_created 1.562364777766845e+09
# HELP my_inprorgress_requests CPU Load
# TYPE my_inprorgress_requests gauge
my_inprorgress_requests 65.0

Python3脚本

from prometheus_client import start_http_server, Summary, Gauge
import random
import time

# Create a metric to track time spent and requests made
REQUEST_TIME = Summary("request_processing_seconds", 'Time spend processing request')

@REQUEST_TIME.time()
def process_request(t):
    time.sleep(t)

if __name__ == "__main__":
    start_http_server(8000)
    g = Gauge('my_inprorgress_requests', 'CPU Load')
    g.set(65)

    while True:
        process_request(random.random())

Answer 1

虽然不是很常见的用例，但是您确实可以从容器连接到主机。

来自https://docs.docker.com/docker-for-mac/networking/

我想从容器连接到主机上的服务

主机的IP地址正在更改（如果您没有网络，则没有IP地址）   访问）。从18.03开始，我们的建议是连接到   特殊的DNS名称 host.docker.internal ，解析为内部   主机使用的IP地址。这是出于发展目的，将   在Docker Desktop以外的生产环境中无法运行   Mac。

Answer 2

供可能通过搜索找到此问题的人参考，现在从 Docker 20.10 及更高版本开始支持。见以下链接：

How to access host port from docker container

和：

https://github.com/docker/for-linux/issues/264#issuecomment-823528103

Prometheus（在Docker容器中）无法在主机上擦除目标

2 个答案: